Organic electroluminescence devices are capable of obtaining light emission with high luminance intensity with low voltage driving, and thus have been actively researched and developed. Generally, organic electroluminescence devices are composed of an organic layer including a light emitting layer, and a pair of electrodes having the layer therebetween, and utilize, for light emission, energy of the exciton generated as a result of recombination of electrons injected from a cathode and holes injected from an anode in the light emitting layer.
Improvement in the efficiency of devices has been recently made by using a phosphorescent light emitting material. For example, an organic electroluminescence device having improved light emission efficiency and heat resistance has been studied, using an iridium complex or a platinum complex as a phosphorescent light emitting material.
Further, doping-type devices, which utilize light emitting layers in which a light emitting material is doped in a host material, have been widely employed.
For example, Patent Document 1 discloses a compound containing a benzothiophene structure and a triphenylene structure as a host material used together with a phosphorescent light emitting material, and discloses that an organic electroluminescence device having high durability is obtained by using the material even when driving at a high current density (a current density of 25 mA/cm2 or more, 40 mA/cm2 in Examples of Patent Document 1).
In addition, Patent Document 2 discloses a compound having a benzothiophene structure or a compound having a carbazole structure and a triazine structure as a material used in an organic layer, and discloses that an organic electroluminescence device having excellent light emission efficiency and durability is obtained by using the material particularly in a light emitting layer or a hole transporting layer.